Move a bunch more things into util package

A lot of utility code was just being imported willy-nilly from one
package to another. This moves the common code into util to make things
more sensible. The code moved were

 * The AsyncQueue and AsyncDecoupledCrossing from junctions.
 * All of the code in rocket's util.scala
 * The BlackBox asynchronous reset registers from uncore.tilelink2
 * The implicit definitions from uncore.util

src/main/scala/uncore/tilelink/Crossing.scala

@@ -1,7 +1,7 @@
 package uncore.tilelink
 
 import Chisel._
-import junctions._
+import util._
 
 object AsyncClientUncachedTileLinkCrossing {
   def apply(from_clock: Clock, from_reset: Bool, from_source: ClientUncachedTileLinkIO, to_clock: Clock, to_reset: Bool, depth: Int = 8, sync: Int = 3): ClientUncachedTileLinkIO = {

src/main/scala/uncore/tilelink/Definitions.scala

@@ -4,9 +4,9 @@ package uncore.tilelink
 import Chisel._
 import junctions._
 import uncore.coherence.CoherencePolicy
-import uncore.util._
-import scala.math.max
 import uncore.constants._
+import util._
+import scala.math.max
 import cde.{Parameters, Field}
 
 case object CacheBlockOffsetBits extends Field[Int]

src/main/scala/uncore/tilelink/Drivers.scala

@@ -4,6 +4,7 @@ import Chisel._
 import junctions._
 import uncore.constants._
 import uncore.util._
+import util._
 import cde.Parameters
 
 abstract class Driver(implicit p: Parameters) extends TLModule()(p) {